Dental-engine handpiece



narran STATES OFFICE..

PnNNsYLvANIA.

DENTAL-ENGINE HANnrInoE.

Specification of Letters Patent.

Patented Mar. 7, 1922.

Application filed November 12, 1920. Serial No. 423,650.

To all whom t may concern.'

Be it known that I, WILL R. PORTER, a citizen of the United States, and a resident of Prince Bay, in the county of Richmond, State of New York, have invented certain new and useful Improvements in Dental- Engine Handpieces, of which the following is a specification, reference being had to the accompanying drawings.

My invention relates particularly to that class of handpieces in which the tool-actuatingV parts are belt-driven, and whi-ch are commonly known as all-cord handpieces. i

Handpieces of the all-cord type as heretofore constructed were provided with a toolengaging chuck which was actuated to clamp the tool by means of a threaded shank arranged tobe actuated by a thumbnut whereby it. wasadvanced or retracted with respect to said chuck to clamp or un` clamp the tool as desired.

The principal object of my invention is to provide an all-corddor belt-driven handpiece with chuck Operating mechanism actuated to clamp a tool by a relative axial slid- .ing'movement of certain of the handpiece parts.

Other objects of my invention are to provide a handpiece of the type contemplated with means to prevent the .sheath from rotating with the rotary'spindles but permitting it to freely oscillate with the natural working movements of the hand of the operator.

My invention further comprehends' novel means for permitting the ready injection of lubricating oil and retaining it in and about the spindle bearing.

Specifically stated, the form of my inven- Y vtion as hereinafter described, comprehends an'all-cordor` belt-driven handpiece comprising a clutch 'actuated Vto clamp a.` tool by means o-f a pivoted lever cooperative with thepin'clined surface of a wedge, and slidably movable with respect thereto; a beltdriven; spindle for rotating said clutch, having a bearing mountedin a support and capable of oscillation therein, but prevented from rotation with said spindle by acoiled spring interposed between said bearing and its supp-ort, said support being provided with an oil chamber whose inlet is normally closed-.by a: spring plate yieldinglyf engaging `the inner wall of ,said chamber.

My invention also includes all of the various novel features of` construction and arrangement as hereinafter more definitely specified. i In the accompanying' drawings, Figure 1 is av central longitudinal sectional view of a handplece constructed in accordance with my invention; F 2 is a similar longitudinal sectional view of said handpiece having its relatively movable clamp-actuating parts axially extended to clamp the chuck on the tool; Fig. 3 is a fragmentary perspective view of the universal connection between the driving shaft and wedge slide or coupling; Fig. l is a fragmentary sectional view ytaken axially of said handpiece on the line fle-Ji. in Fig. l; and Fig. 5 is a transverse sectional view taken throu line 5-5 in rF ig. l'.

In said figures, the handpiece comprises` the forward tubularspindle l engagedgby the wedge slide or coupling 2 with-the` back spindle or drivingr 4shaft 3, and ar-` ranged to be rotated thereby within the casing comprising the tubular sheath or hand-hold 4 which is slidably mounted on the back spindle bearing or slide 5 by its threaded connection with'the sleeve'or collet 6 which is mounted to slide longitudinally on said bearing or slide 5.

The sleeve or collet 6 is in threaded enconveniently provided withV the keyway 9" into which the collet key: 10 in thecollet 6 may extend tO prevent the relative rotation their free relative movement in an axial.` or longitudinal direction.` f,

The slide or bearings;,5` has iti-rear end enlarged to provide a boss 12 against which the spindle pulley lf3 ont-he hack spindle` or` driving shaft 3 rotates, and said vboss`fis flanged to provide an annularspacelet ar-yv ranged to catch. any drippingsofoil which may ooze out between the back spindle or driving shaft 3 and its bearing-. The-bearsv ing or slide 5 is arranged to'be rotatably supported in the wrist vJoint frame .rittension,44

Tian s. s. WHITE DENTAL gh the oil chamber on' ther gagement with the rear end of the sheath 4,

y925 of said collet 6 and slide 5, but permitting` which is carried by the wrist joint frame 16 of well known construction.

' The forward end of the wrist joint .frame extension isprovided with the threaded boss 17 which conveniently carries the tubular shield 19 extended forwardly 4and disposed in telescopic relation with the sheath or handhold 4, andserving` as a protection'to-they exposed oily exterior surface of the slide 5 when the sheath 4l is extended with respect to said slide 5 as shown in Fig. 2, to clamp Y the tool as hereinafter described.

The bearing or slide 5 is prevented from rotating with the back spindle or driving shaft 3 by the `coiled spring 20 which is interposed between'the forward end of the Wrist joint frame extension and theshoulder 21 formed by the overhanging' head 22 of the nut which is in threaded engagement with the bearing 5 and arranged to hold the spring under compression to provide sufficient friction to prevent the slide 5 and the sheath 4 carried thereby from rotating with the rotary spindle ordi-wing` shaft 3,

but permitting them to freely oscillate with the natural working` movements of the hand of the operator.

Thefwrist Joint frame extension is pro-v vided with the annularoil chamber 25V surrounding the slide or bearing 5 and has'the oil inletA aperture `26"\vhich vis normally closed by the oilhret-aining' shutter 27 com`` pri'sing the sheet metal` spring which is curved to conform to and closely engage theV inner wall of said chamber 25 and liasone end 29 bent laterally to engage a suitable recess or-notch 30 in the inner wall of said chamber 25, as best showin in Fini. v The slide or bearing 5 is provided with thefoil aperture 32 opening into the oil chamber 25 andlarranged to admit oil between the back spindle ordriving shaft Bjand its bearing.`

The lforward endof the back spindle or driving shaft 3 vis enlargedto form the cylindrical head 35 and is provided with the 'undercuttransversely extending slot "86, which is` arranged to receive `the T-lieaded projection 37 ofthe wedge slide or coupling;

2 fittedV therein with sutlicient looseness toA afford a substantially universal oint wherei Vby the rotation ofthe back spindle or driving shaftjS effects therotation of said wedge slide or coupling 2. l

Said wedge slide 2 is provided ward end Vwith the proyecting lkey or spline 'Y 40 extending into a suitable slot oi' lreyway 41 in the Wall of the forward spin d le 1 which is mounted for rotation in the' sheath 4. The

forward end ofsaidyforwarhd Spindle 1 is supported in the conical bearing 43, and the back end is 'arranged to rotate inthe bearing bushing i in the wall of(V provided by the cylindricalV sheath 44mounted in the recess 45 the boreof. said sheath 4. in end thrust bearing washer 46 is disposed inthe bore of the sheath 4 and affords an end thrust l bearing .for the forward spindlel. y l

The forward spindle 1 is provided with Athe transversely disposed slot 47 intersecting theV slot 41 and serving as a bearing for the .trnnnions 49 of the lever 50, which is disposed for oscillation in the slot 51 in the wedge slide or coupling 2, and which has its free end inclined to bear against the serrated wall 52 ofsaid slot, so thatsaid free end may engage any one of the serrations and serve to lock. the parts of vthe handpiece in their Vrelatively ,adjusted vpositions when extended7 as shown in Fig. 2.

The lever 50 is arranged to effect Vthe clamping of the-,tool in the'chuck 56,

which is longitudinally split and provided at it-sopposite ends with conical surfaces respectively arranged to bear against similarly inclined conical surfaces 57 and 58, respectively formed in the bore of the forward spindle Land in the bore of the plunger F9,` which carries the plunger tip 60 ar-` ranged to be engaged by the elbow 61 oft-he lever 56, so that whenthe relatively` slidable members of the handpiece are shifted to jcause the .lever v50 to rideupon the ser-V rated wall 52, the elbow 61 forces the plunger 59 forwardly against the chuck 56 andby cooperation ofthe conical ends of said chuck withtheoonical surfaces 57 and 58..,it l

is contracted to embrace the tool 55'tl1erein withA such pressure as to firmly `hold said tool in its operative position.

62 which registers witha suitable opening V63 in the slide for tlieinjectionof oilinto the annular chamber 65 between the driving shaft 3 and its bearing in the slide 5,*formed by the reduced; rebfrion`66 of saidgdriving shaftf. 'Said oil hole 62 is normally covered by the sheath 4 andlis accessible by the mere removal of'saidsheath.

The boss 12 of the slide 5 is conveniently provided withV the aperture 67" into whichl a bodkin or othersuitableitoolmay be inserted torv holding said boss when it is desired to` remove or sepa-rate the relative rotation. t

' It willV be readily wear-of the partsin theirbearings may be handpiece parts i by 10() The collet 6 is provided with the oil hole seen that the slightest taken uptby loosen'ingthe sheath-adjusting nut, 7 and rotating the sheath 4`on the collet i 6 until the ustment Aofthebearings is at'-, tained 4which ustnient may be i'naintained by jamming the slieathadjusting `nut v7 into` engagement with the'vfend ofmthesheath 4. Said sheath nut y7 may preferably be split as showy atv 70 and by its spring pressure tightly clamps the `collet 5`.

Y lli/ly invention is advantageous in ythat the parts of vthe handpiece may be taken apart and assembled by the Eremoval:lof a single set screw 69 andthe sheath '4, Whicliper- .mits the withdrawal ofthe back spindle or driving shaft 3 from its bearing in the slide 5, and when thus released from said bearing,`the wedge slideQJ may be separated from said baclrspindle ordriving shaft 3 by simply slidinglthem oppositely ina lateral direction to release the T-head 37 on said wedge-slide 2, fromthe undercut slot 36 in the head 35 of the back spindle or driving shaft 3L n Furthermore, by 'the'construction herein contemplated, the space between the relatively slidable members is bridged by the shield 15, so-as to protect the oily exterior surface ofthey slide 5, and thereby prevent the hands ofthe operator from being soiled by contact therewith.

do not'desire to limitmy invention to the precise details of Vconstruction and arrangement as herein set forth, as it is obvious that various modifications may be made therein without departing from the essential features of my invention as defined in the appended claims. y

Having thusy described invention, I claim f` l. A belt-driven dental engine handpiece having a tool-engaging clutch actuated to gripe-nd release a tool bya lever movable longitudinally on an inclined surface.

- 2; A'belt-drivendental engine handpiece having relatively movable tool V clamping means arranged to be actuated to clamp and release a tool .byf'relatively sliding said means longitudinally by aforward and backward movement of the hand of the operator.

3. A belt-driven dental engine handpiece having a sheath, a tool-engaging clutch rotatably mounted in said sheath, a supporting frame, and yielding means tendingfto prevent the rotation of said shea-th with said clutch, but permitting its relative rotary movement with respect to said frame.

4. A belt-driven dental engine ha-ndpiece comprising a driving shaft. tool-holding means connected to be rotated by said driving shaft, a bearing for said driving shaft, a support for said bearing, and a spring interposed between said support and bearing tending to frictionally prevent the rotation of said bearing with said shaft but permitting the relative rotary movement of said bearing and support.

5. A beltdriven dental engine handpiece comprising "a driving shaft, tool-holding means connected to be rotated by said driving sha-ft, a bearing for said driving shaft, a support for said bearing having an annular oil chamber embracing said bearing, and having an inlet extended through the wall of said support, and a shutter for said inlet comprising a sheet spring tending to engage the wall of said chamber and normally close said inlet.

6. A. belt-driven dental. engine hadpiece comprising a driving shaft, toolholding means connected to be rotated by said"`driv`V ing shaftfa bearing for said drivingshaftl having an l'oil hole therein, asupportfor said bearing providedwith an annular `oil chamber embracing said bearing and having an inlet extended throughithe wall of said. support, and a yieldingy shutter for said inlet substantially conforming to the wall of aid chamber and tending to close said in- 7. A belt-driven dental engine handpiece comprising a driving shaft, tool-holding means connected to be rotated by said driving shaft, a bearing for said 'driving' shaft having an oil hole extendedtherethrougli,`a support for saidT bearing comprising. an an nular oil chamber disposedin communication with said oil' hole, and having a recess or notch therein and an inlet extending throughthe wall thereof, and a shutter for said inlet comprisingya sheet spring substantially conforming to the wall of said chamber tendingto close said inlet and having one end thereof extended into said notch or recess to prevent itsaccidental displacement.

S. Ina denta-Iengine handpiece, the `e0rn bin'ationv with" a driving shaft having a belt or cord'pulleythereonfby which it Vmay be rotated', cfa. bearings for said driving shaft providing alslide, a sheath supported by said slide and arranged tobe shifted axiallythereon, a tool lholdingclutch rotatably mounted insaidsheath and connected to4 be rotated by 4'said driving "Shaft, and means 'compris` ing a lever actuated by the longitudinal movement of said sheath on said bearing to effect the clamping or the releasing of said tool.

9. In a dental engine handpiece, the combination with a driving shaft having a cord pulley thereon by which it is rotated, of a bearing for said driving shaft providing a slide, a sheath supported by said slide and arranged to move axially with respect thereto, a tool-holding clutch rotatably mounted in said sheath, and a connection comprising a substantially universal lioint between said clutch and driving shaft whereby said clutch is rotated, and means actuated by the relative longitudinal movement of said sheath and said slide to effect the opening and closing of said chuck. n

l0. In a dental engine handpiece, the combination with a driving shaft having a cord pulley thereon by which it is rotated, of a bearing for said driving shaft providing a slide, a support for said bearing, a spring interposed between said bearing and its support tending to prevent the rotation of said bearing with said shaft but permitting its relative rotatable movement with respect to said support, a collet longitudinally movable on said slide, a sheath carried by said collet, a hollow spindle rotatably mounted in Said sheath, `'means comprising a universal Ijoint connecting said hollow spindle with said drivingshaft', a tool-engaging clutch carried by said spindle, and means effected by the bearingr with said shaft but permitting its relative rotation with respect to said sup;

port, a eollet'longitudinally movable on said slide, a sheath carried by said collet, a hollow spindle rotatably Vmounted insaid sheath, a Wedge slide connecting` said spin-` dle Withi-'saiddriving shaft and comprising a universal joint, a tool chuck 'carried by said spindle, and a lever cooperative With said Wedge slide arranged to actuate said clutch to grip and release a tool bythe longitudinal `movement of said collet ony said slide. ,i i

12. In a dental enginehandpiece, the oombnation with a driving shafthavinga cordv pull-ey thereon 4by Which it is rotated, of a bearing, forfsaidtdriving shaft-providing a slideya supportfor said bearing, a spring interposed"betweenV said bearing and its support, tending to prevent the rotation of said bearing` with said shaft but permitting its `relative rotation With respect to `said support, a collet longitudinally movable on said slide, a. sheath carried by said collet, a hol` low spindle rotatably 'mounted in f said sheath, a Wedge slide connecting said 'spindle with 'said driving shaft and comprising a universal joint, a tool chuck carried by said spindle, and a levez` cooperative `With said Wedge slide arranged to actuated said clutch to grip ,and release a tool bythelongitudinal movement of said vcolleton said slide7 and a shield carried by said support arranged to protect the surface of said slide when said collet and said slide are relatively Y extended. y Y

13. In a dental engine handpiece the combinationrvvith a driving shaft, of a bearing for said driving shaft, means carrying' an operative tool actuated by said driving shaft, a support in which said bearing;v is rotatably mounted, a nut in threaded engagementivith said bearing adjustable toward and from said support, and a spring interposed between said nut'` and said support' tending to prevent said bearingr from rotating with said shaft but permitting its rotary movement with respectto said sup.-

port.

litnesses: 1 i

SAMUEL R. BARTON, CLIFTON C. HALLQWELL.'

ln Witness whereof; IV havewhereunto set. my hand this `10thV jday ofNovernberLAyD.;

` Winnn roiirnn I 

